Interlocking system for high frequency transmitters



Oct. 13, 1931. L. A. GEBHARD INTERLOCKING SYSTEM FOR HIGH FREQUENCYTRAN-SMITTERS Filed Dec.

23, 1929 2 Sheets-Sheet INVENTOR.

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E i Emma Oct. 13, 1931. L. A. GEBHARD 1,326,766

INTERIJOCKING SYSTEM FOR HIGH FREQUENCY TRANSMITTERS Filed Dec. 23, 19292 Sheets-Sheet 2 IN V EN TOR. am a. 906 M),

&mrfi9\vm%l AiTORNEY Patented Oct. 13, 1931 UNITED STATES [PATENT OFFICELOUIS A. GEBHARD, OF WASHINGTON, DISTRICT: OF COLUMBIA, ASSIGNOR TOWIRED RADIO, INC., OF NEW YORK, N. Y., A CORPORATION OF DELAWAREINTERLOCKING SYSTEM FOR HIGH FREQUENCY TRANSMITTERS Application filedDecember 23, 1929. Serial No. 416,157.

My invention relates broadly to frequency changing systems for highpower transmitters and more particularly to an interlock circuit for aninductance system.

One of the objects of my invention is to pro- Vide a frequency changingsystem for high power electron tube transmitters where inductance unitsof different values may be interchanged in the transmitter and cooled bythe circulation of the cooling fluid which passes around the ackets ofthe high power electron tubes, with interlocking controls operative tostop the flow of cooling fluid during the periods between which theinductance units are being interchanged.

Another ob ect of my invention is to provide a system of interlockingswitches for actuation by the movement of the fluid cooled frequencychange system of a high power transmitter, where valve mechanism isactuated during the periods intermediate the frequency change operationfor cutting off the flow of cooling fluid through the frequency changesystem and reestablishing the flow when a selected inductance unit ofthe frequency change system has been properly positioned and connectedin the transmitter circuit.

Still another object of my invention is to provide a protectiveinterlocking system for frequency change switches in which the parts ofthe frequency change apparatus must be mechanicall positioned in properposition before the ow of the cooling fluid may be established and thecircuits through the frequency change apparatus com leted.

Other and further objects 0 my invention reside in the electricalinterlock circuit and protective system set forth more fully in thespecification hereinafter following by reference to the accompanying"drawings in p which Figure 1 illustrates schematically the arrangementof frequency change apparatus and electrical interlock system thereforembodying the principles of my invention; Fig. 2 is a side view of theswitchin device which opens the electrical circuit through the frequencychange system during the rotative movement of the inductance supportingframe; and Fig. 3 is a fragmentary view showing the operation of thecoupling means for interconnecting a selected inductance unit with thefluid cooled jackets of the high power tubes in the transmitter andillustrating the circuit interlock, which is closed when the inductancesystem is in operative position and opened when the coupling meansbetween the inductance and the high power tube jackets are shifted forthe release of a particular inductance from connection with the fluidconductive conduits adjacent thereto.

In my copending application, Serial No. 406,709, filed November 12,1929, for inductance systems, I have described the details ofconstruction of a fluid cooled inductance change system, wherein amechanical coupling system is provided between a set of fixed fluidconveying conduits for establishing mechanical connection with theinductance units of different values formed of fluid conveying tubingwhich are carried by a frame structure which is shiftable in position tobring a selected inductance unit into register and coupling connectionwith the fixed fluid conveying conduits.

I have found that in operating the frequency change systems of thecharacter described in the aforesaid copending applicationit isessential to control the flow of the cooling fluid to prevent thecooling fluid from flowing out of the open connections in the fixedconduits during the process ofchanging frequencies. It is also necessaryto protect the transmitter so that the transmitter cannot be starteduntil the parts of the frequency change switch are locked in properposition. I provide a plurality of interlocking switches all of whichmust be closed before it is possible to start the transmitter. A circuitcloser is operated by the movement of the main support'of the inductancesystem into position. Another circuit closer is operated as the frame ofthe frequency change system is rotated, the circuit being closed onlywhen an inductance unit is aligned with the fixed terminals and pipeconnections adj acent the inductance frame. A further circuit closer iscontrolled by the coupling actuating means which connect the fluidsupply and delivery conduits adjacent the inductance system with aselected tubular inductance unit. The circuits thus controlled operate asolenoid which controls the fluid supply valve, cutting off the flow offluid through the cooling system if predetermined conditions have notbeen met. At the same time the anode potential in the transmittercircuit is cut off so that unless predetermined conditions are fully metthe transmitter will not operate and the cooling fluid does notcirculate.

Referring to the drawings, reference character 1 indicates a rotatableframe carrying inductance coils 2, 3, 4 and 5. The frame is arranged torotate about a shaft 6 located at the center of the frame and arrangedparallel with the axes of the coils. The structure of the frame andinductance coils will be more fully understood from my hereinbeforereferred to copending application Serial Number 406,709. Thecoolingfluid for the inductance coils enters pipe line 7 and then passesthrough electrically operated valve 8, from there into insulated tubingcoil 9 and through the coupling connection 10 into inductance coil 2.The cooling fluid spreads at this point so as to pass to both ends ofinductance coil '2 into the cooling jackets 46 and 47 of the fluidcooled tubes at 11 and 12. After passing through these jackets thecooling fluid returns through llw and 12a through the coil 2 meeting atthe connection 13 and passing out through insulated tubing coil 14 anddischarging through outlet 15. A flow or pressure indicator 16 isconnected into the fluid circuit just beyond electrically operated valve8. Pressure indicator 16 has a pair of contacts 48 which may be soadjusted that if the pressure or flow falls below a certain value thesecontacts will be closed. The solenoid coil 17 of electrically operatedvalve 8 is energized from source 18 through contacts 19,

. 19a, 20, 20a, contactor 21 and switch 22. Contacts 19 and 19a are soarranged that when frame 23 which supports coils 2, 3, 4 and 5 is rockedto disengage a particular coil the contacts 19 and 19a are opened. Thecontacts 19 and 19a are closed when the frame 23 is returned to theproper position. Contacts 20 and 20a are shown more clearly in Fig. 2and are so arranged that when frame 1 is rotated in frame 23 thecontacts 20 and 20a are opened by means of spring member 50 having a cam51 which is shifted by means'of the cam faces or notches 52 in disc 53to open or close contacts 20 and 20a. When the frame lating arms 26, 27,and 28 and through levers 29, 30, 31, 32, 33 and 34. Lever 29 has ameans of lockingits adjustment through slots 35 and 36 which engage witha projection in the front panel 37. Lever 29 has a handle 38 whichpermits operation by an attendant. Lever 29 carries a projection whichoperates to close contacts 21 when the locking devices are closed. Thesecontacts may conveniently be supported on panel 37 as shown in Fig. 3.These contacts are arranged to be closed when the locking devices areclosed and opened when the locking devices also are opened.

A momentary contact switch is shown at 39, a relay at 40, with a currentlimiting resistor at 41. Relay 40 has contacts 42 and 43 which areopened when the coil 40 is deenergized and closed when the coil isenergized. Contact 42 is a hold contact which serves to connect the coilof relay 40 to source 18 after the momentary contact switch has beenclosed. Contact 43 is connected in serics with the anode supply 44 forthe high power tubes of the radio transmitter. This supply passesthrough radio frequency choke 45 to a center connection of coils 2, 3, 4and 5, and thence to the anodes of the tubes 46 and 47.

In operating the circuit of my invention the attendant closes switch 22.If contacts 19, 20 and 21 are properly closed, coil 17 of electricallyoperated valve 8 will be energized. This permits the cooling fluid topass through its normal circuit. Flow or pressure indicator.16 isactuated, which opens contacts 48, removing the short circuit from coilof relay 40. The attendant then presses the start button of themomentary contact switch 39 which energizes the winding of relay 40,closing contacts 42 and 43. The attendant may now release the startbutton of momentary switch 39 for contact 42 will energize the coil ofrelay 40. Contact 43 being closed the anode potential from source 44 isconnected to the transmitter circuit.

Suppose now that the attendant attempts to shift frequency withoutopening the proper switches. He will move the lever 29 to disengage thecoil 2. This automatically opens contacts 21 which will de-energize coil17 of electrically operated valve 8. Valve 8 will close cutting off thefluid supply to coil 2 and to the indicator. Contacts 48 will c ose,short-circuiting the coil of relay 40. Relay 40 will thus bedeenergized, and contacts 42 and 43 will open, thus preventing furtherenergization of the coil of relay 40. The opening of contacts 43 alsoopens the anode circuit to the anodes of the vacuum tubes, thuspreventing breakage of contacts 2 with high voltage connected to them.Suppose now the operator has shifted frequency but has neglected to setframe 1 in its proper position. The operator will be unable to start thetransmitter and close the fluid cooling circuit because contact 20isopen. Similar action occurs if the operator neglects to rock frame 23back to its proper position for contact 19 in this case would be open.If the operator forgets to lock the lever 29 contacts 21 would be openwhich would prevent the operator starting the transmitter.

The several safety devices which I provide on the transmitter insureboth the protection I made and that no limitations upon my inven tionare intended other than are imposed by the scope of the appendedclaims.- a

What I claim as new-and desire to secure by Letters Patent of the UnitedStates is as follows:

1. In a frequency changing system for high frequency transmitters, meanscarrying a multiplicity of tubular inductance units of differentinductance values, a fluid cooling system having fluid conveyingconduits extending therefrom, a set of fluid supply and deliveryconduits, means for re 'stering a selected inductance unit with saifluid conveying and supply and delivery conduits, and circuitcontrollers actuated by said aforementioned means for electricallyde-energizing the circuits of said frequency changing system until aselected inductance unit is effectively coupled with said fluid coolingsystem.

2. In a frequency changing system, a multiplicity of tubular inductanceunits of different inductance values, a cooling system including fluidconveying and sup ly and delivery conduits terminating a jacent saidtubular inductance units, means for selectively couplin said tubularinductance units with said con uits, a plurality of circuit controllers,and means actuating said circuit controllers for completing theelectrical cir-' cuits through said frequency changing system when aselected tubular inductance unit is mechanically coupled with said fluidconveyin supply and delivery conduits.

3. n a frequency changing system, a multiplicit of tubular inductanceunits of different in uctance values, a cooling s stem including fluidconveying, supply an delivery conduits terminating ad'acent said tubularinductance units, means or selectively coupling said tubularinductance'units with said conduits, a plurality of circuit controllers,and means actuated by said circuit controllers for opening theelectrical circuits to said frequency changing system when a selectedinductance unit is uncoupled from said fluid ing, supply and deliveryconduits. n a frequency changing system for high frequency-transmitters,a multiplicity of inductance units of different values each having meansfor circulating cooling fluid therethrough, a multiplicity of fluidconveying conduits terminating inpositions with which said inductanceunits may be selectively registered, means for controlling the flow offluid through said fluid conveying conduits, and electrical means forcutting off the flow of fluid when said inductance units are out ofregister with said fluid conveying conduits.

5. In a high frequency signaling system, a frequency changer including aframe structure, a multiplicity of inductance units carried bysaid'frame structure each having different inductance values, amultiplicity of fluid conveying conduits positioned adjacent said framestructure, means for aligning a conve selected one of said inductanceunits with respect to said fluid conveying conduits for coupling saidinductance units with said fluid conveyin conduits, a valve system forcontrolling t e flow of cooling fluid throu h said fluid conveyingconduits and throug a selected inductance unit registered therewith, andmeans controlled by the movement of said frame structure for cutting offthe flow of cooling fluid intermediate the periods of interchange of oneinductance unit with another inductance unit in coupled relation withsaid fluid conveying conduits.

6. In a frequency changing system, a frame structure, a rotatablecarrier supported by said frame structure, a multiplicity of inductanceunits of different frequency characteristics supported by said rotatablecarrier, a pluralit of fluid conveying conduits positioned a jacent saidframe structure, means for angularly shifting'said frame structure androtatably moving said rotatable carrier for selectively aligning aparticular inductance unit with said fluid conveying conduits,

coupling means for mechanically coupling said fluid conveying conduitswith a selected one of said inductance units, and a multiplicity ofelectrical circuits controlled by the angular movement of said framestructure,

the rotative movement of said rotatable carrier and the operation ofsaid coupling means for cutting off the flow of cooling fluid throughsaid fluid conveying conduits and deenergizing the circuits through aselected indi m ncerunit.

7. In a frequency changingsystem, a

be aligned with said fluid conveying conduits, said inductance units andthe terminals thereof being of hollow tubular construction for thecirculation of a cooling fluid therethrough, means for coupling aselected inductance unit with said fluid conveying conduit-s,electromagnetic means for controlling the flow of cooling fluid throughsaid fluid conveying conduits, and an electrical circuit effective uponthe proper positioning of said frame structure, the proper rotation cfsaid rotatable carrier and the proper operation of said coupling meansfor cutting on the flow of cooling fluid and/establishing a circulatorypath for cooling fluid through the selected inductance aligned with saidfluid conveying conduits.

8. In a frequency changing system, a frame structure shiftable to eitherof two limiting positions, a movable carrier on said frame structure, amultiplicity of inductance units each having different frequencycharacteristics and being constituted by a hollow tubular conductorhaving fluid conveying terminals projecting therefrom, a multiplicity offluid conveying conduits, means for coupling the projecting terminalsof'a selected inductance unit with said fluid conveying conduits,electrical means connecting said coupling means for establishing acirculatory passage for cooling fluid through said fluid conveyingconduits and a selected inductance unit, said means being controlled bythe rotative movement of said movable carrier and the angular movementof said frame structure, whereby the flow of cooling fluid is cut offwhen said frame structure is shifted to one of its limiting positionsand the selected inductance unit is out of alignment with said fluidconveying conduits.

9. In a frequency changing system, a multiplicity of inductance unitshaving different frequency characteristics, means for rendering aselected one of said inductance units effective while the others of saidinductance units are ineffective, means for circulating a cooling fluidthrough a selected inductance unit having electrical means for renderingthe operation of said cooling means ineffective when all of saidinductance units are ineffective. and rendering the operation of saidcooling means effective when one of said inductance units is renderedeffective.

10. In afrequency changing system, a movable frame structure, amultiplicity of inductance units each having different frequencycharacteristics and carried by said frame structure, cooling means forcirculating a cooling fluid through a selected inductance unit, andmeans controlled by the movement of said frame structure forelectrically controlling the operation of said cooling means foreffectively maintaining a selected inductance unit at predeterminedtemperature while said inductance unit is energized by high frequencycurrent.

11. In a frequency changin system, a frame structure, a multiplicity oinductance units of different frequency characteristics supported bysaid frame structure, coolin means for circulating a cooling fluidthroug a selected inductance unit, a power supply circuit and meanscontrolled simultaneously with the connection of said power supplycircuit to a selected inductance for initiating the circulation of acooling fluid through the selected inductance unit.

12. In a frequency changing system, a movable frame structure, amultiplicity of inductance units each having different frequencycharacteristics carried by said movable frame structure, a power supplycircuit, said movable frame structure being shiftable to effectivelyconnect a selected inductance unit with said ower supply circuit and tosimultaneously su ject the selected inductance unit to the effect of acooling fluid, and means controlled by the movement of said framestructure for disconnecting the power supply circuit from the selectedinductance unit and interrupting the flow of cooling fluid thcrethrough.

-LOUIS A. GEBHARD.

